Energy Economics Basics

Levelized Cost of Energy

The levelized cost of energy (LCOE) is the standard metric for comparing electricity generation costs across different technologies. LCOE calculates the total lifetime cost of building and operating a power plant (including capital expenditure, financing costs, fuel, operations and maintenance, and decommissioning) divided by the total electricity produced over its lifetime, expressed in dollars per kilowatt-hour. This normalization allows fair comparison between technologies with very different cost structures: a solar farm has high upfront capital costs but zero fuel costs, while a natural gas plant has lower capital costs but ongoing and volatile fuel expenses.

As of 2025, the global average LCOE for utility-scale solar PV is approximately $0.04/kWh, onshore wind is $0.04/kWh, offshore wind is $0.08/kWh, natural gas combined cycle is $0.05 to $0.07/kWh, and coal is $0.07 to $0.14/kWh. These averages mask significant regional variation: solar LCOE in the sunny Middle East or Chile can be as low as $0.015/kWh, while projects in northern Europe or areas with permitting challenges cost more. The key trend is that renewable LCOEs continue to decline while fossil fuel LCOEs fluctuate with commodity prices and generally trend upward as extraction becomes more difficult and carbon regulations tighten.

LCOE has important limitations as a comparison metric. It does not account for the time-varying value of electricity (solar electricity produced at midday when supply is abundant may be worth less than electricity produced during evening peak demand). It does not capture system integration costs (storage, transmission upgrades, backup capacity needed for variable renewables). And it excludes externalities like health damages from air pollution, climate change costs, and water contamination. More comprehensive metrics like the levelized cost of storage-adjusted electricity (LCOS-adjusted LCOE) and social cost of energy (which includes externalities) provide more complete comparisons but are harder to calculate with certainty.

Learning Curves and Cost Declines

Learning curves, also called experience curves, describe the consistent relationship between cumulative production volume and unit cost observed in manufactured technologies. Solar PV has a learning rate of approximately 24%, meaning that each doubling of cumulative installed capacity reduces module costs by about 24%. This relationship has held remarkably consistently over four decades and across a 10,000-fold increase in cumulative deployment, from roughly 1 MW globally in 1977 to over 2,000 GW in 2025. The result has been a cost decline of over 99%, from roughly $76 per watt in 1977 to below $0.20 per watt today.

Lithium-ion batteries follow a learning rate of approximately 18 to 20%, with pack prices falling from over $1,100/kWh in 2010 to approximately $130/kWh in 2025. Wind turbines have a more modest learning rate of 12 to 15%, reflecting the mix of manufactured components (blades, generators, which follow strong learning curves) and site-specific civil works (foundations, roads, grid connections, which have less room for learning-driven cost reduction). Fossil fuel technologies, being mature and based on commodity fuel inputs, do not benefit from learning curve cost declines; their costs are primarily driven by fuel prices and regulatory requirements.

The predictability of learning curves enables forward-looking investment decisions and policy design. If solar PV continues to follow its historical learning curve, module costs will fall below $0.10 per watt before 2030, making solar the cheapest energy source in virtually every location on Earth. Battery costs following their learning curve would reach $50 to $70/kWh by 2030, making four-hour battery storage cheaper than any peaking generation technology and enabling widespread adoption of solar-plus-storage systems that provide dispatchable clean electricity around the clock. These projections are not speculative; they extrapolate from decades of consistent empirical data.

Subsidies, Externalities, and True Costs

All energy sources have received government subsidies throughout their development, though the magnitude and persistence of support varies enormously. The International Monetary Fund estimated global fossil fuel subsidies at approximately $7 trillion in 2022, including both explicit subsidies (direct payments, tax breaks, below-market fuel prices) and implicit subsidies (unpriced environmental and health damages). Explicit fossil fuel subsidies alone total roughly $1.3 trillion annually, far exceeding renewable energy subsidies of approximately $300 to $400 billion per year globally. These subsidies distort energy markets by making fossil fuels appear cheaper than their true social cost.

Externalities are costs or benefits imposed on third parties who are not directly involved in a transaction. Fossil fuel combustion generates negative externalities including climate change damages (estimated by the U.S. government at roughly $50 to $200 per tonne of CO2), air pollution health costs (respiratory disease, cardiovascular disease, cancer), water contamination from mining and drilling, and ecosystem degradation. When these externalities are internalized through carbon pricing or regulatory requirements, the full social cost of fossil fuel electricity rises by roughly $0.05 to $0.20/kWh for coal and $0.01 to $0.05/kWh for natural gas, making renewables even more decisively cost-competitive.

Renewable energy also generates externalities, though they are far smaller in magnitude. Manufacturing solar panels and wind turbines produces emissions and waste that should be accounted for (though lifecycle emissions are 20 to 100 times lower per kWh than fossil fuels). Land use for solar and wind farms affects ecosystems and landscapes. Mining lithium, cobalt, and rare earth elements for batteries and generators creates localized environmental impacts. Honest energy economics requires accounting for all externalities across all technologies, which consistently shows renewables imposing far lower total social costs per unit of energy delivered.

Market Dynamics and the Energy Transition

The energy transition creates both value destruction and value creation on enormous scales. Fossil fuel assets, including coal mines, gas pipelines, oil refineries, and thermal power plants, face the risk of becoming stranded assets if their remaining useful life is cut short by the transition to clean energy. Carbon Tracker estimates that $1 to $4 trillion in fossil fuel assets could become stranded under various transition scenarios. Conversely, clean energy investment reached approximately $1.8 trillion globally in 2024, exceeding fossil fuel investment for the first time, creating new industries, supply chains, and employment at enormous scale.

The duck curve, first identified by the California Independent System Operator, illustrates a key economic challenge of high solar penetration. As midday solar generation floods the grid, wholesale electricity prices collapse (sometimes going negative), reducing the revenue earned by all generators including solar. Meanwhile, a steep evening ramp occurs as solar output fades just as residential demand peaks, requiring fast-responding generation or storage. This price pattern creates economic incentives for battery storage (charge during cheap midday solar, discharge during expensive evening peak), demand flexibility (shift consumption to midday), and west-facing solar installations (which produce more evening generation than south-facing panels).

Energy market design is evolving to accommodate the unique characteristics of renewables and storage. Marginal cost pricing in wholesale markets, designed for fuel-burning generators with meaningful variable costs, produces very low or zero prices when renewables with near-zero marginal costs dominate supply. Revenue sufficiency for the investment needed to build and maintain clean energy systems may require complementary mechanisms including capacity markets (paying for availability), long-term contracts (power purchase agreements that provide revenue certainty for project financing), and carbon pricing (which increases the cost of competing fossil generation). The optimal market design for a predominantly renewable system remains an active area of policy research and experimentation worldwide.